Texas ? A venomous viper that vanished twice in the past month has turned up again after a one-week absence from its Texas aquarium.

Moody Gardens spokeswoman Jerri Hamachek says the missing 10-inch African bush viper was found Friday night outside the visitor center entrance. Hamachek says officials believe someone left the snake there.

The viper disappeared Aug. 8 from the venomous snake exhibit. The same snake went missing for two days last month until workers found it hiding atop a metal screen that seals the top of the enclosure.

The first time, officials thought the snake had escaped on its own. The second time, they called police because the fastener holding the padlock to the exhibit appeared to have been tampered with.